Hot-rolled steel
Hot-rolled steel is formed hot into standard structural sections (UB, UC, PFC) to AS/NZS 3679.1, usually Grade 300 and designed under AS 4100, unlike cold-formed steel.
Ask Chalkline about this →Hot-rolled steel is steel formed at high temperature, above its recrystallisation point, then rolled into standard structural sections: universal beams (UB) and columns (UC), parallel flange channels (PFC), and angles. In Australia these sections are produced to AS/NZS 3679.1:2016, and the residential and general structural default is Grade 300 (300 MPa minimum yield strength). For example, a 200 UB 25 lintel or a steel post carrying a load-bearing wall is a hot-rolled section.
Hot-rolled is distinct from cold-formed steel, which is shaped from thin sheet at room temperature into light-gauge sections such as residential wall studs and top-hat battens. The two are not interchangeable: hot-rolled structural members are designed under AS 4100, while cold-formed framing is designed under AS/NZS 4600, and specifying the wrong family is a common drafting error. Cold-formed hollow sections such as SHS and RHS sit under AS/NZS 1163 (typically Grade C350), separate again from the hot-rolled open sections.
Hot-rolled sections are the default where a load or span exceeds what timber or LVL can carry, where a fire rating drives the design, or where a beam is also a visible architectural element. The section size is the engineer’s call from the structural drawing; the builder’s decisions are coating (galvanising or powdercoat for exposure) and connections (welded, bolted, or end-plate). See steel beams for the section families, coatings, and typical lead times.
Also known as: Hot-rolled structural steel, hot-rolled sections, HR steel.
Category: Materials / Structural steel.
Related
See also
- AS 4100 (steel structures design)
- AS/NZS 4600 (cold-formed steel)
- Universal beam (UB)
- LGS (light gauge steel)
References
- AS/NZS 3679.1:2016 Structural steel Part 1: Hot-rolled bars and sections, Standards Australia (verified 2026-05-15)
- InfraBuild Hot Rolled product guide (verified 2026-05-13)
Last updated: 2026-05-30. Verified: 2026-05-15. Quarterly review for currency.